/**
 * 访问web_test数据库
 */

const mysql = require('mysql');
const pool = mysql.createPool({
    connectionLimit : 10,
    host            : "127.0.0.1",
    user            : "root",
    password        : "020820",
    database        : "web_test"
});

/**
 * 获取SQL执行结果
 * @returns {Promise}
 */
function query(sql, values) {
    return new Promise((resolve, reject) => {
        // 连接池中获取连接
        pool.getConnection((error, connection) => {
            if (error) {
                reject(error);
            }
            else {
                // 执行SQL语句
                connection.query(sql, values, (error, results) => {
                    // 释放连接
                    connection.release();
                    if (error) {
                        reject(error);
                    }
                    else {
                        resolve(results);
                    }
                });
            }
        });
    });
}

module.exports = { query };